Cutting the bottom branches on Fir trees?

[wisconsitom]

@routestep, definitely worthwhile to prune out multi tops and such.  Do you know if white pine weevil is present in your area?  That pest also messes with spruce terminal leaders and can be the cause of forking.  Not too hard to control if acreage not too large.

[mjeselskis]

@routestep, definitely worthwhile to prune out multi tops and such.  Do you know if white pine weevil is present in your area?  That pest also messes with spruce terminal leaders and can be the cause of forking.  Not too hard to control if acreage not too large.

@wisconsintom I'd be very interested in hearing your advice on the white pine weavil. I have a stand of 8 yr old planted white pine that they are really messing up the tops. I keep pruning the dead leaders out and leaving the best branch on the next row down to grow as the new leader. The bugs just keep picking another tree to attack.

[wisconsitom]

Hi mjeselskis.  Yes, on our planted white pines and Norway spruce, the tip weevil adult female is still sleeping, in the duff layer.  But in just weeks, concurrent with the bright yellow blossoms of the forsythia bush, if you know what that landscape shrub is.....she'll crawl or fly (?) up to the terminal buds of white pines and especially Norway spruce if present, and lay her eggs.  These will hatch and the larvae will tunnel around feeding.  A few weeks later, you'll be walking your rows, admiring the new growth when you will come to your best trees, the ones with the most vigor and the largest terminal buds, and see 2 or 3 feet of new growth bright orangey brown, dropping off to the side dead.  The tree responds by making multiple leaders, i.e. forked tops.  In my experience, the same trees will often be repeatedly attacked.

In a few weeks, when those yellow blooms appear here in town on forsythia bushes, I'll go up and spray the tips down to first whorl of branches, and anything that looks like a leader or growing tip, on any white pines and Norway spruces I can reach with my backpack sprayer, using a synthetic pyrethroid called bifenthrin, with a spreader-sticker, to keep the stuff around thru spring rain and snow. 

I can't remember the trade name of the bifenthrin formulation.  The spreader-sticker is called Tactic, it's just lecithin.  This combo inhibits the adult female from laying her eggs up there.  After 3 or 4 years of treating, our pressure has gotten much less, just tiny bits of damage.  Huge difference.

If you can find him, Rick Schulte of Crop Production Services, located in Deforest, WI is some kind of genius at this stuff.  If he's still there-I'm retired now and have lost track-he'll set you up with exactly what you need.  You might have resources like that in your area.

[mjeselskis]

Hi mjeselskis.  Yes, on our planted white pines and Norway spruce, the tip weevil adult female is still sleeping, in the duff layer.  But in just weeks, concurrent with the bright yellow blossoms of the forsythia bush, if you know what that landscape shrub is.....she'll crawl or fly (?) up to the terminal buds of white pines and especially Norway spruce if present, and lay her eggs.  These will hatch and the larvae will tunnel around feeding.  A few weeks later, you'll be walking your rows, admiring the new growth when you will come to your best trees, the ones with the most vigor and the largest terminal buds, and see 2 or 3 feet of new growth bright orangey brown, dropping off to the side dead.  The tree responds by making multiple leaders, i.e. forked tops.  In my experience, the same trees will often be repeatedly attacked.

In a few weeks, when those yellow blooms appear here in town on forsythia bushes, I'll go up and spray the tips down to first whorl of branches, and anything that looks like a leader or growing tip, on any white pines and Norway spruces I can reach with my backpack sprayer, using a synthetic pyrethroid called bifenthrin, with a spreader-sticker, to keep the stuff around thru spring rain and snow.

I can't remember the trade name of the bifenthrin formulation.  The spreader-sticker is called Tactic, it's just lecithin.  This combo inhibits the adult female from laying her eggs up there.  After 3 or 4 years of treating, our pressure has gotten much less, just tiny bits of damage.  Huge difference.

If you can find him, Rick Schulte of Crop Production Services, located in Deforest, WI is some kind of genius at this stuff.  If he's still there-I'm retired now and have lost track-he'll set you up with exactly what you need.  You might have resources like that in your area.

Thank you. We have a forsythia bush in the yard. I'll keep an eye on it. I'll definitely try the treatment you suggested. I'm tired of these things taking out the best trees

[wisconsitom]

Good deal.  I never wanted to plant thousands of trees and then have to spray them with insecticide but once I understood the deal, it became a reasonable thing to do.  It's not so bad, just a little bit at treetop.  These pyrethroids act almost as much as repellants as they do as actual killers, though they certainly will knock back the population.  Worst is spraying taller trees up overhead.  Shifting breezes and gravity means some drift'll get ya.  I grin and bear it-with my mouth closed-and just try and get the job done fast.  Usually wear my worst junk and toss afterward. 

I'm led to believe the weevil can keep messing with your trees up into the 15-20ft. height range.  Not sure that's quite it, but in any case, I'm likely going to spray just one more time, this spring, then go free range.

Pruning out forked tops down to best leader is good to do.  I catch that before I spray.  Why apply material to something that will get cut off?

Best of luck.   Like I said, on limited acreage, this is quite feasible.  On big tracts, I don't know.....drones?

[jimbarry]

Pruning whether a 1 inch stub or to the branch collar will increase the probability of rot in spruce and fir. It's just not done. I have a back yard full of pruned spruce my father trimmed up 30 years ago, all full of rot.  :

Results of a stub grown over in pine.


 

[wisconsitom]

@SwampDonkey, not doubting you, but wondering, if pruning lower branches off spruce and fir can often lead to rot pockets, why would making what amount to improper pruning cuts-for all species-by leaving two inch stubs beyond the collar be preferable to simply making the cut just beyond the collar, like normal?

In trial after trial, this has been shown to be the way to minimize decay.  What am I missing?  Dr. Shigo is leaning up on one elbow in his grave, waiting for your response😆.

[SwampDonkey]

Instead of a dead 6 foot limb, now you have a 2" one beyond the collar. ;D

You want trees with very small limbs your pruning when pruning fir and spruce for logs and small diameter young ones that show good growth. Anything bigger than your finger and you'll wish you left alone. I don't know who Dr. Shigo was, was he pruning pines? Well, first article in Google search below I looked up. ;D

Quote from an article where he stated:

"Natural target pruning" just outside that collar -- no more flush cuts, which expose vulnerable trunk wood to insects and pathogens."

[source: Tree Friendly Pruning]

What I'm suggesting doesn't seem any different than Shigo. You don't want to be in that collar wood. 2" leaves a little buffer against tear into that collar. So 1/4" -2" if you want. I always go within the 2" rule myself. ;D

Any questions?? ;D

I've observed 8 year old fir pruning and the scars have been totally healed over, nub and all. Now what that will look like inside when sawed in a few years will likely yield some surprises, where larger limbs are a lot more ugly than small ones. I know in the past, pruning larger limbs than your finger, do not have great results. The tree is nice and healed and looks nice on the lawn but not that great as lumber.

Hit the trees with the saw when young, small diameter and vigorous, at least 15 feet tall. Not suppressed stuff. This is generally in thinned stands or plantations where spacing was 6-7 feet when established, spruce and fir. Pine is likely wider spaced, less shade tolerant. Open grown fir and spruce, don't waste the time thinking it will be a log tree. The limbs are too fat and they are full of internodal shoots between whorls.

[wisconsitom]

It's just as easy to make the cut in the right place.  Stubs, even two inchers, invite decay, not prevent it.

I don't care if anybody prunes their stuff or not.  But why not do it right if you're doing it?

That would be my question.😏

[SwampDonkey]

Got to leave a stub, if your not cutting into the collar. The doc said beyond the collar, not flush to it. ;) If it was going to be rotten, than every natural spruce log that self pruned would be rotten, which isn't true.

[wisconsitom]

We're going to have to agree to disagree.

Scratch that, it's not me you're disagreeing with, it's the entire tree care industry.

[SwampDonkey]

So be it.

[beenthere]

Leave the collar, nothing beyond the collar, and have the best possible outcome. 

May just as well drop the argument about rot, as it has little to do with the objective to clean up the trees of bottom branches. 

[SwampDonkey]

I think potential rot has to be considered, I see no reason why to exclude it. It's certainly on people's minds the entire thread.